Mark Kermode's DVD round-up

I wrote previously in this column of the "subversion" of the documentary format by films as diverse as Catfish, I'm Still Here and Exit Through the Gift Shop, all of which provoked heated debate about authenticity versus artifice. Yet, adventurous as they may be, none of these titles come close to the generic redefinition of The Arbor (2010, Verve, 15), an extraordinarily impressive meditation upon the short life and troubled legacy of gifted playwright Andrea Dunbar. Indeed, whether this masterfully assured feature debut from director Clio Barnard even qualifies as a documentary at all remains a matter for debate, the strange mix of fact and fantasy being closer in tone (although not form) to the equally indefinable Waltz With Bashir.

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At the centre of Barnard's mercurial film is a dramatic device which sounds like it shouldn't work at all: a series of intimate audio interviews with the late Dunbar's friends and family, to which accomplished actors perform note-perfect lip-synched (and carefully choreographed) "readings". If you find that hard to imagine, don't worry; it's every bit as bizarrely baffling to watch, and no easier to describe. The effect is haunting, disorientating and at times profoundly uncomfortable as we struggle to distinguish between the often seamless blends of documentary and drama. Yet within that struggle there lurks a truth – an unavoidable awareness that even "factual" first-person reportage and eyewitness accounts are themselves dramatic constructions, stories retold and reinterpreted, each tale shaped by their teller.

Interspersed with these interviews are public performances of Dunbar's work, presented on the Buttershaw estate in Bradford before the watchful gaze of contemporary residents of the playwright's old stomping ground. Archival audio-visual material completes the picture, adding a third textual layer to Barnard's effortlessly complex structure and presenting the viewer with yet another version of recorded reality. Somehow the disparate elements form a strikingly cohesive whole, conjuring a portrait of the artist and her offspring which is both emotionally engaging and stylistically radical. The only disappointment is the scantness of the DVD extras, comprising a trailer (which makes The Arbor look more like an ominous horror movie) and a short film about horse-racing on public roads, which the sport's protagonists insist is "not illegal" but which nevertheless incurs the attentions of the police.

Is Jackass 3 (2010, Paramount, 18) a documentary? On one level it clearly fulfils the generic criteria, providing an eyewitness account of a series of events which "actually happened" in the real world. Yes, a man really did attach a remote controlled helicopter to his penis with a piece of string to see if it would hurt (it did). Yes, some young gentlemen really did allow their naked skins to be bonded together and then forcefully ripped apart to see if superglue really does "lock tight" like it says on the packet (it does). And yes, some asshole really did allow themselves to be locked into a Portaloo full of human excrement which was then bungeed into the air, covering the vomiting victim in a tidal wave of shit. In cinemas, this latest catalogue of superannuated adolescent masturbation was presented in 3D, meaning that the volcanic eruptions of diarrhoea, urine and sick splattered out of the screen toward gagging audiences. While a stereoscopic "explosive extended" edition is included in the "triple-play" blu-ray pack, bog-standard 2D DVD viewers won't feel any less queasy as laugh-out-loud knockabout slapstick gives way to barf-out-loud jock-homoerotica and bum-crack-sweat-licking toilet humour. You don't need silly glasses to know when to look away. "Animals are used in some of the stunts," observe the BBFC with customary detachment, "although none of them are mistreated." The same, sadly, cannot be said of either the human cast or their audience.

You could be forgiven for mistaking Pedro González-Rubio's wonderfully naturalistic Alamar (2009, New Wave, U) for a documentary, although this verité gem is in fact a deceptive drama. Before going back to living with his single mother in Rome, a young boy spends "quality time" with his father in the Mexican Caribbean, exploring the coral reefs around the Mayan fishing villages of the Banco Chinchorro, learning about a way of life which seems to come from another era. It's gentle, lyrical fare; an enchanting rites-of-passage tale whose observational style lends an air of utter authenticity. I had to keep reminding myself that it wasn't true: – although on some level, of course, it was.

Despite the fact that there were only 28 days in February, 2010 saw the release of two movies entitled Leap Year. The first was one of the worst films of the year, a horribly formulaic transatlantic romcom in which Amy Adams ships up in a pastiche boggy Oireland peopled by Blarney-spouting natives and Guinness-drinking dark horses. The second was Michael Rowe's provocative Mexican anti-love story Leap Year (2010, Axiom, 2010), a startling but surprisingly compassionate account of seething loneliness which manifests itself through a series of sadomasochistic encounters. Monica del Carmen is heartbreakingly convincing as Laura, the struggling journalist with a fractured past who watches life through the window of the sparse apartment to which she brings a succession of men for supposedly casual sex. When an encounter with one such partner touches a self-destructive nerve, Laura finds a way to explore her carefully calendered chronicle of a death foretold. Despite some painfully explicit scenes of consensual degradation, the tone of Rowe's movie remains admirably unexploitative and ultimately forgiving.

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